What is a Cup Mute?

A cup mute is a type of brass instrument mute that is placed in the bell of instruments such as the trumpet or trombone to soften and modify the tone. It features a cup-shaped attachment that partially covers the bell, which alters how the sound waves leave the instrument.

The cup-shaped section sits close to the bell and reduces the brightness of the sound, producing a mellow, muted, and slightly veiled tone. Many cup mutes are adjustable, allowing players to move the cup closer to or farther from the bell to change the degree of muting.

Cup mutes are commonly used in jazz bands, orchestras, and studio recordings to create a softer and more subdued brass sound. Composers and arrangers often use them to blend brass instruments more smoothly with woodwinds or to achieve a distinctive tonal color.